Article
Polymer Science
Mahdi Boudaghi, Brian J. J. Edwards, Bamin Khomami
Summary: The temporal and spatial evolution of shear banding in polyethylene solutions was studied during startup and steady-state shear flow. A high-fidelity method was developed to simulate and evaluate this phenomenon. The study observed transient shear banding during startup flow, with inhomogeneous concentration distribution within the system.
Article
Polymer Science
Niels Holten-Andersen, Bradley D. Olsen, Irina Mahmad Rasid, Ameya Rao
Summary: The study investigates the effect of entanglements on chain dynamics in a model associative network, showing that entanglements have a significant impact on self-diffusion and relaxation. These results demonstrate the marked effects of entanglements on network performance.
Article
Polymer Science
Konstantin I. Morozov, Alexander M. Leshansky
Summary: This paper presents theoretical modeling of transport through crowded heterogeneous viscous environments and derives analytical expressions for the frictional resistance of particles in polymer solutions. The study shows that for particles with adhering polymers, the frictional resistance is Stokesian, while for particles with nonadsorbing polymers, the frictional resistance is strongly non-Stokesian, depending on the network mesh size and the depletion layer thickness. The theoretical predictions are in good agreement with experimental results.
Article
Multidisciplinary Sciences
Jan Smrek, Jonathan Garamella, Rae Robertson-Anderson, Davide Michieletto
Summary: The study reveals that larger supercoiling in dense supercoiled DNA increases the size of entangled plasmids and enhances DNA mobility. These findings suggest a way to tune DNA mobility via supercoiling, enabling topological control over the (micro)rheology of DNA-based complex fluids.
Article
Polymer Science
Dejie Kong, Sourya Banik, Michael J. San Francisco, Megan Lee, Rae M. Robertson Anderson, Charles M. Schroeder, Gregory B. McKenna
Summary: Bulk rheology measurements on concentrated monodisperse ring-linear DNA mixtures are reported for the first time. The behavior of these mixtures is compared with that of pure linear DNA, highlighting the dominant role of linear chains in the dynamics and entanglement scaling of the blends.
Article
Chemistry, Physical
Prateek Dwivedi, Atishay Shrivastava, Dipin Pillai, Rahul Mangal
Summary: Biological swimmers often encounter fluids containing dissolved macromolecules, making them non-Newtonian. Active droplets simulate the propulsion characteristics of biological swimmers and provide insights into their locomotive strategies. This study investigates the motion of an active oil droplet driven by micellar solubilization in a polymer-rich aqueous medium, revealing the sensitivity of droplet motion to macromolecules. In situ visualization of the chemical field highlights the breakdown of continuum approximation due to size differences. The Peclet number captures transitions in propulsion modes, and particle image velocimetry reveals a mode switch from pusher to puller propulsion.
Article
Polymer Science
Yexin Zheng, Mesfin Tsige, Shi-Qing Wang
Summary: In this study, molecular dynamics simulations were used to investigate the entanglement lockup phenomena in the uniaxial melt stretching of entangled polymer melts. The results revealed that under high strains, the entanglement network became increasingly tighter, leading to chain tension and the formation of network junctions. It was hypothesized that the interchain entanglement at junctions can lockup as long as certain conditions are met. This study provides insights into the mechanical properties of polymer materials.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Michael C. Burroughs, Yuanyi Zhang, Abhishek M. Shetty, Christopher M. Bates, L. Gary Leal, Matthew E. Helgeson
Summary: This study experimentally confirmed the concentration profile of entangled polymer solutions under shear, demonstrating the critical importance of flow-concentration coupling in such systems. The findings showed that at shear rates above a critical value, concentration and velocity profiles can develop bands, consistent with model predictions.
PHYSICAL REVIEW LETTERS
(2021)
Article
Polymer Science
Aijie Han, Ralph H. Colby
Summary: The dynamics of polyelectrolyte solutions have been studied experimentally and theoretically, showing that at predicted entanglement concentrations, the response of the polyelectrolyte solutions appear unentangled. At higher concentrations in entangled solutions, the behavior of polyelectrolyte solutions resembles that of solutions of neutral polymers. Four methods for evaluating entanglement concentration have been compared, with results similar to those of neutral polymer solutions.
Article
Mechanics
Enny Tran, Andrew Clarke
Summary: It is generally understood that the entanglement effects of viscoelastic polymer solutions are weakened under strong flow. However, recent research has found that high molecular weight HPAM solutions, which are entangled at use concentrations, exhibit a characteristic relaxation time when transitioning to elastic turbulence in porous flow. In this study, we directly measure the apparent characteristic relaxation time under shear using controlled-stress parallel-superposition background shear, and our results align with previous calculations using Rolie-poly and Rolie-double-poly models.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2023)
Article
Polymer Science
Konstantin Morozov, Alexander M. Leshansky
Summary: Accurate physical modeling of heterogeneous complex fluids is important for understanding transport in biological and biomimetic environments. This paper investigates the frictional resistance of a rigid object moving through an entangled polymer solution using a two-fluid model. Different boundary conditions and their effects on frictional resistance are analyzed. The study shows that the generalized Stokes relation holds for strongly adherent polymer, but not for particles pre-treated to hinder polymer adhesion.
Article
Mechanics
Manfred H. Wagner, Esmaeil Narimissa, Qian Huang
Summary: The study extends the criterion for brittle fracture of entangled polymer liquids by considering the effects of finite chain extensibility and polymer concentration. Experimental data and models support the finding that crack initiation originates from the rupture of C-C bonds, leading to the fracture of polymer chains and crack propagation.
JOURNAL OF RHEOLOGY
(2021)
Article
Polymer Science
Fan Wang, Lu-Kun Feng, Ye-Di Li, Hong-Xia Guo
Summary: Dissipative particle dynamics (DPD) is a promising method for studying entangled polymers, but its applicability as a model for ideal chains and accurate description of entangled melts is not well understood. In this study, we comprehensively investigate the structure, dynamics, and linear viscoelasticity of a DPD entangled model system, specifically a semiflexible linear polymer melt. Our results show that the DPD model accurately predicts the monomer motion and relaxation behavior of entangled polymers, following the predictions of reptation theory. However, there are some limitations to the reptation theory, as evidenced by anomalous sub-diffusive motion and cross-correlation between chains. Overall, the semiflexible linear DPD model is able to capture the static and dynamic properties of entangled polymer melts.
CHINESE JOURNAL OF POLYMER SCIENCE
(2023)
Article
Physics, Particles & Fields
Denis Arruga, Olivier Minazzoli
Summary: In this manuscript, analytical external spherical solutions of entangled relativity are presented and compared to numerical solutions in a Tolman-Oppenheimer-Volkoff framework. Both types of solutions match perfectly outside spherical compact objects, validating their accuracy. The analytical external solutions, which depend on only two parameters, can be used to easily calculate observables such as X-ray pulse profiles without needing knowledge of the object's internal equation of state.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Chemistry, Multidisciplinary
Paula Malo de Molina, Thu Phuong Le, Amaia Iturrospe, Urs Gasser, Arantxa Arbe, Juan Colmenero, Jose A. Pomposo
Summary: The study reports the preparation method of neat bovine serum albumin (BSA) single-chain nanoparticles (SCNPs) through denaturation in urea and intramolecular cross-linking. Two disuccinimide ester linkers (DSG and DSS) were used for internal cross-linking, and the degree of cross-linking was monitored using 1H NMR spectroscopy. This method is applicable to a wide range of compact proteins and paves the way for the synthesis of biodegradable protein SCNPs for applications in nanomedicine.
Article
Chemistry, Multidisciplinary
Joerg G. Werner, Hyomin Lee, Ulrich Wiesner, David A. Weitz
Summary: Polymeric microcapsules with mesoporous shells containing uniformly sized nanopores are achieved through self-assembly of amphiphilic block copolymers with a selective porogen in double emulsion drops. The microcapsules can withstand harsh conditions and exhibit pH-responsive permeability to polymeric solutes, showing potential for tunable macromolecular separation and purification as a filtration medium. Further control over shell permeability is achieved through a dual-phase separation method to fabricate microcapsules with hierarchically porous shells.
Article
Polymer Science
Sarah A. Hesse, Peter A. Beaucage, Detlef-M Smilgies, Ulrich Wiesner
Summary: The study reports a one-pot synthesis method for obtaining carbon materials with asymmetric pore structures, demonstrating a combination of asymmetric, hierarchical pore structures and well-defined mesoporosity throughout the material. The materials show potential for various applications in energy conversion and storage, separations, and catalysis.
Article
Chemistry, Multidisciplinary
R. Paxton Thedford, Peter A. Beaucage, Ethan M. Susca, Corson A. Chao, Katja C. Nowack, Robert B. Van Dover, Sol M. Gruner, Ulrich Wiesner
Summary: By using ceramic templates derived from bulk block copolymer self-assembly, a versatile method for synthesizing mesostructured metals is demonstrated, showing emergent quantum-scale phenomena. High-pressure infiltration of bulk block copolymer self-assembly based ceramic templates enables the study of high-quality metals with previously inaccessible architectures, paving the way for block-copolymer derived quantum metamaterials.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
William R. T. Tait, R. Paxton Thedford, Dana Chapman, Fei Yu, Judson W. Freidl, Ekaterina S. Sablina, Gavin M. Batsimm, Ulrich B. Wiesner
Summary: Two ultralarge pore-size carbons with 3D network architectures were synthesized, showing promise for future design as electrode materials in electrochemical energy storage devices.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Karnika Singh, Ankit Yadav, Prateek Dwivedi, Rahul Mangal
Summary: The study investigates the motion of active SiO2-Pt Janus particles in a complex environment of passive silica tracers, revealing significant impacts of collisions on the swimmers' motion. The frequency and nature of collisions determine the overall impact of tracers on the active particles, with high-density tracers leading to novel organizational behavior of tracers around the active particles.
Article
Chemistry, Physical
Fei Wu, Thomas C. Gardinier, Melik Z. Turker, Feng Chen, Pei-Ming Chen, Aranapakam M. Venkatesan, Vaibhav Patel, Gregory P. Adams, Michelle S. Bradbury, Ulrich B. Wiesner, Geno Germano, Kai Ma
Summary: This study reports a chemical approach to covalently link chemotherapeutic drugs and targeting moieties to a poly(ethylene glycol) (PEG)-coated ultrasmall silica nanoparticle platform, achieving high drug loading capacity and favorable biodistribution and pharmacokinetics profiles.
CHEMISTRY OF MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
R. Paxton Thedford, Fei Yu, William R. T. Tait, Kunal Shastri, Francesco Monticone, Ulrich Wiesner
Summary: This review explores the opportunities and challenges of using soft matter science to synthesize quantum materials with advanced properties, highlighting existing work at the interface of these two fields and providing perspectives on future directions.
ADVANCED MATERIALS
(2023)
Review
Materials Science, Multidisciplinary
Prateek Dwivedi, Karnika Singh, Kartik Chaudhary, Rahul Mangal
Summary: This article provides a review on the current status and future trends of artificial adhesives. Inspired by natural adhesives, researchers have designed and fabricated artificial adhesives that possess self-cleaning, antifouling, and reusability characteristics in both wet and dry environments. Polymers are the predominant material choice, and various fabrication techniques have been employed to mimic the bioadhesion mechanism. These artificial adhesives hold great potential in various applications.
ACS APPLIED POLYMER MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Fei Wu, Pei-Ming Chen, Thomas C. Gardinier, Melik Z. Turker, Aranapakam M. Venkatesan, Vaibhav Patel, Tin Khor, Michelle S. Bradbury, Ulrich B. Wiesner, Gregory P. Adams, Geno Germano, Feng Chen, Kai Ma
Summary: An ultrasmall folate receptor alpha (FR alpha) targeted silica nanoparticle (C'Dot) drug conjugate (CDC) was developed to address the limitations of current systemic drug delivery for cancer management. The lead candidate formulation demonstrated specific targeting, multivalent binding properties, enzymatic responsive payload cleavage, stability in human plasma, rapid clearance, and minimal organ retention. It also showed superior efficacy in tumor penetration, cytotoxicity, and therapeutic outcome in various tumor models expressing different levels of FR alpha.
Article
Polymer Science
Sarah A. Hesse, Kevin E. Fritz, Peter A. Beaucage, Ethan M. Susca, Jin Suntivich, Ulrich Wiesner
Summary: This article presents a method for preparing asymmetric porous materials using copolymer and non-solvent induced phase separation (CNIPS) technique, and investigates the influence of thermal processing on the structure and properties of these materials. The results show that changing the processing conditions allows for control of the pore structure and composition of the materials, which affects the performance of the membranes. This study is significant for improving the application of porous materials in energy conversion and storage, separation, and catalysis.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2023)
Article
Polymer Science
Wennie Yun Lee, Dana Chapman, Fei Yu, William R. T. Tait, R. Paxton Thedford, Guillaume Freychet, Mikhail Zhernenkov, Lara A. Estroff, Ulrich B. Wiesner
Summary: Self-assembled block copolymer thin films and their nanocomposites have diverse applications due to their nanostructures. Optical super-resolution microscopy (OSRM) has emerged as an alternative method for characterizing nanoscopic polymer morphology. This study focuses on self-assembled triblock terpolymer thin films with all three blocks exposed at the top surface, and demonstrates the use of OSRM for multicolor characterization of chemically distinct nanodomains.
Article
Chemistry, Physical
Jacob A. Erstling, Nada Naguib, Joshua A. Hinckley, Rachel Lee, Grant B. Feuer, James F. Tallman, Lieihn Tsaur, Danni Tang, Ulrich B. Wiesner
Summary: Fluorescent labeling of cellular substructures using antibody-organic dye conjugates can be improved by conjugating widely available secondary antibodies and cationic species to ultrasmall different color dyes. These dyes show enhanced brightness and photostability compared to their parent dyes. By optimizing the conjugation and labeling protocols, three-color super-resolution microscopy imaging with improved resolution can be achieved.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Prateek Dwivedi, Atishay Shrivastava, Dipin Pillai, Rahul Mangal
Summary: Biological swimmers often encounter fluids containing dissolved macromolecules, making them non-Newtonian. Active droplets simulate the propulsion characteristics of biological swimmers and provide insights into their locomotive strategies. This study investigates the motion of an active oil droplet driven by micellar solubilization in a polymer-rich aqueous medium, revealing the sensitivity of droplet motion to macromolecules. In situ visualization of the chemical field highlights the breakdown of continuum approximation due to size differences. The Peclet number captures transitions in propulsion modes, and particle image velocimetry reveals a mode switch from pusher to puller propulsion.
Article
Chemistry, Physical
Prateek Dwivedi, Atishay Shrivastava, Dipin Pillai, Naveen Tiwari, Rahul Mangal
Summary: The motion of biological swimmers in bodily fluids can be modeled using active droplets driven by micellar solubilization in a viscoelastic polymeric solution. By varying the surfactant and polymer concentration, the viscoelastic nature of the medium can be adjusted. At moderate Deborah numbers, the moving droplet exhibits a steady deformed shape and at higher Deborah numbers, time-periodic deformation and oscillatory transition in swimming mode are observed. This study unveils the previously unexplored complexity in the motion of active droplets in viscoelastic fluids.
Review
Nanoscience & Nanotechnology
Jorg G. Werner, Yuanzhi Li, Ulrich Wiesner
Summary: The multiscale architecture of electrochemical energy storage materials plays a critical role in device performance. The pore space of electrodes at nanoscale to macroscale determines mass transport and energy density. The size of charge-storing materials affects stability, capacitive charge storage, charge-transfer resistance, efficiency, and degradation. The use of block copolymer self-assembly provides nanoscale control and insights into the correlations observed in electrochemical energy storage.